Devices which use an electrochemical pump to deliver a fixed quantity of liquid drug have been described. For example, U.S. Pat. No. 3,894,538 to Richter (Jul. 15, 1975) describes among other things a device for supplying medicines which includes a container having an opening for ejecting medicine therefrom, the container being associated with another container, the size of which can be increased by, for example, the generation of gas particles by electrolytical gas development within the container.
Somewhat similar devices are described in various patents to Maget. E.g. U.S. Pat. Nos. 4,522,698 to Maget (Jun. 11, 1985) and 4,902,278 to Maget et al. (Feb. 20, 1990).
A problem associated with such devices is that they require a relatively large amount of electrical energy to generate rather limited amounts of gas, which gas is used to displace the medicine containing liquid contained within the drug container or reservoir. Furthermore, the devices require relatively large amounts of energy to generate gas at a higher rate. It would be an improvement in the art to have a device which had the advantages (e.g. fine control of flow rate) of electrochemical gas generation to generate larger amounts of gases and/or higher rates of gas generation with fewer of the associated disadvantages (e.g. relatively large energy, power and space requirements).